This is a study of facial feminization surgery given to ten Iranian trans women during the years 1990-2007. It provides a good description of the various procedures they used to feminize the face, although not all of the patients needed all of the possible surgeries.
The authors talk about the importance of having standards for FFS. They present a staged surgical protocol and parameters to consider before surgery.
The study includes a table summarizing some facial differences between males and females. It is interesting to note that the differences are measured in millimeters. This may be why some people can pass without surgery.
The authors mention the importance of cephalometeric radiography (this may refer to X-rays) and tracing in planning the surgery.
The authors make the interesting observation that the changes needed to feminize the face will vary by ethnicity and society.
The average age of the trans women in this study was only 23 (range 20-32). This is younger than in many of the other studies.
The before pictures are in black and white while the after pictures are in color. Nevertheless, it is easy to see that the face in the after pictures is much rounder. The after picture was taken four years after the operation, so there might have been other causes for the change (hormones or weight gain).
As in other studies, the authors are the surgeons who performed the surgery, thus they may have a bias to want to believe that the surgery was successful.
The article includes an interesting discussion of transgender history. Prior to 1991, there was no medical treatment for transgender people in Iran. In 1991 a religious decree was issued saying that transition was a permitted therapeutic procedure.
The authors conclude with an endorsement of further research:
Although our patients were satisfied with their improvement in appearance with these standard set of operations, conclusions as to these effects cannot be drawn. Even if feminization is considerable, the degree of improvement these procedures have on lifestyle remains to be assessed.